Complementary hydrogen bonding of a carboxylato-barbiturate with urea and acetamide: experimental and theoretical approach

Spectrochim Acta A Mol Biomol Spectrosc. 2011 Dec;83(1):532-9. doi: 10.1016/j.saa.2011.08.079. Epub 2011 Sep 9.

Abstract

A barbiturate derivative, 4-(2,4,6-trioxo-tetrahydro-pyrimidine-5-ylidenemethyl)-benzoic acid (L1) possessing functional complementarity to amides has been synthesized and characterized. Its binding separately with urea and acetamide was monitored using UV-vis, fluorescence and (1)H-NMR spectroscopic titrations. Experiments suggested stronger binding of L1 with urea as compared to acetamide. The solid adducts of L1 prepared separately with urea and acetamide were also characterized using IR, (1)H-NMR spectral and PXRD techniques. Theoretical studies on hydrogen bonded complexes of L1-urea and L1-acetamide in the gas phase, aqueous, and DMSO medium were carried out using density functional theory (DFT) at the B3LYP/6-31G** level. The theoretical calculations agreed to the experimental results.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Acetamides / chemistry*
  • Barbiturates / chemistry*
  • Hydrogen Bonding
  • Magnetic Resonance Spectroscopy
  • Models, Molecular
  • Quantum Theory
  • Spectrometry, Fluorescence
  • Spectrophotometry, Ultraviolet
  • Urea / chemistry*

Substances

  • Acetamides
  • Barbiturates
  • Urea
  • acetamide
  • barbituric acid